- Clinical science
Glomus tumors are rare, benign, painful, blue-red soft tissue neoplasms originating from glomus bodies in the skin. They typically present in adults 20–40 years and are most commonly found in the distal extremities under the nails. Management consists of surgical excision of the lesion, which usually leads to complete resolution. Malignant glomus tumors and metastases are exceedingly rare.
- ∼ 1–5% of all soft tissue tumors of the arms
- Solitary glomus tumors: 20–40 years
- Multiple glomus tumors; : more common in children; ; some are congenital
Epidemiological data refers to the US, unless otherwise specified.
- Autosomal dominant inheritance in most multiple glomus tumors
- Glomus tumors are hamartomatous proliferations of modified smooth muscle cells originating from glomus bodies.
- Malignant transformation (glomangiosarcoma) is extremely rare and typically locally infiltrating.
Glomus tumors are diagnosed clinically; . Imaging procedures assess the size and exact location, while findings of glomus cells in the excised tumor confirm the diagnosis.
- Histology: uniformly round, small, glomus cells with pale eosinophilic cytoplasm associated with vasculature
- Plain radiography: bony erosions in subungual lesions
- Color-duplex ultrasonography; : determines exact size and location of tumor; shows a hypoechoic nodule with prominent vascularity
- Total surgical excision of the lesion; recurrence is rare.
- Venous malformations
The differential diagnoses listed here are not exhaustive.
- Carotid body
Paraganglioma of the middle ear
- Glomus tympanicum
- Glomus jugular
- Vascular tuft
- Definition: benign or malignant, endocrine-active neoplasms, which originate from non‑chromaffin cells of the parasympathetic nervous system
- Paragangliomas are the most common tumors of the middle ear.
- ♀ > ♂ (2:1)
- Complications: infiltration of the jugular foramen (cranial nerves IX–XI) → jugular foramen syndrome
- Otoscopy: red, pulsating ear drum → The tumor is visible through the ear drum and moves in a pulsating manner.
- Audiometry: conductive hearing loss
- MRI: good delineation
- CT: to assess bone involvement of the growing tumor
- Digital subtraction angiography: preoperative to confirm diagnosis and to document the arterial supply
- Somatostatin receptor scintigraphy:differentiation from other vascular processes
- Potentially positron emission tomography (PET): evidence of multiocular growth of the glomus tumor
- Treatment: removal of the tumor (possible via various accessible entry points)